The field research will take Joan and Paul about five months; it will be a long time        we meet them again.[ ]

A. after                            

B. before

C. since                            

D. when

能通过资源权力的让渡为政府带来收入的政策工具是（）。

A.信息劝诫

B.补贴

C.产权拍卖

D.税收